7 ways to tell if someone is cheating on you

First of all, there’s a good chance you’re right — it’s perfectly normal to lie.

But if you’re worried that someone’s fibbing extends into the important stuff, like happiness or fidelity, you might have considered trying to catch them in a lie.

Unfortunately, science can’t tell you if your partner is sleeping around, but it is getting better at spotting when someone — especially a significant other — is being deceptive.

Here are seven ways to tell if your partner might be keeping something important from you.

Ask a friend.

Other people — strangers, even — have an uncanny ability to detect when something’s not right in someone else’s relationship.

BYU psychologists tested out this idea by having couples draw an object together, with one participant blindfolded and the other one giving instructions on what to draw. The whole thing was videotaped. Before they started, the scientists had the couples answer a few questions about their relationship in private, including whether or not they’d ever cheated.

Then, the researchers had a group of strangers watch the footage and guess which couples included a partner who’d ever cheated. The volunteers were surprisingly accurate.

Although preliminary, the research suggests that, simply by watching a couple doing something that requires working together, an outside observer may be able to detect infidelity or unhappiness.

“People make remarkably accurate judgments about others in a variety of situations after just a brief exposure to their behavior,” the researchers wrote in the study.

Mull it over while doing something else.

People are generally bad judges of character — consciously, at least. When we are given time to process another person’s actions subconsciously, however, we’re far better at telling truth from deceit.

In 2013, a team of psychologists had a panel of student judges watch people give testimony and decide if they’d lied or told the truth. The students who were given time to think before they made a decision — so long as they were made to think about something other than the case they were assessing — were better at figuring out whether the person they were judging had been deceitful.

“These findings suggest that the human mind is not unfit to distinguish between truth and deception,” write the researchers in the study, “but that this ability resides in previously overlooked processes.”

Listen carefully to the words they use.

For a recent study, Southern Methodist University professor of psychology James W. Pennebaker looked at some data he and his colleague Diane Berry had gathered from a text analysis program. They found that some specific patterns of language were helpful at predicting when someone was avoiding the truth.

Liars, they found, tended to use fewer of the following three types of words:

First person words, like “I,” “me,” or “my”

Cognitive words, like “realize” or “think”

Exclusive words, like “but” or “except”

But they tended to use more of the following types of words:

Negative emotion words, like “hate,” “anger,” or “enemy”

Motion verbs, like “walk” or “move”

Listen to the sound of their voice.

Canadian researchers recently had a group of volunteers listen to a pair of voices and rate how attractive each speaker sounded. Then, the researchers asked them to judge how likely each person would be to cheat in a romantic relationship.

The female volunteers were most likely to say the men with lower-pitched voices would cheat; the men typically guessed that the women with higher-pitched voices would cheat.

Research has shown that men with more testosterone tend to have deeper voices, and as it turns out, higher levels of testosterone in men have been linked with higher rates of cheating. The jury is still out on whether there is any such association in women, though, and the researchers have yet to link their findings with actual observed behavior.

Pay attention to social media use.

Does your partner spend more time Snap-chatting than talking to you? Recent research suggests that people who are highly active on two other social networks — Facebook and Twitter — may be more likely to have social-media-related conflict, and subsequently more likely to experience “infidelity, breakup, and divorce.” (They haven’t studied Snapchat yet.)

In his study, University of Missouri researcher Russell Clayton studied the social media habits of close to 600 Twitter users. Most people used Twitter for roughly an hour a day, 5 days a week. But those who used it more often than that were more likely to get in arguments with their partners, get divorced, or cheat. The more time they spent on Twitter, the worse the relationship outcomes were.

It’s unlikely that too much tweeting, posting, and liking caused other people to cheat, of course, but if anything the study showed that there’s certainly a connection between the two.

Watch for sudden changes in behavior.

If you’ve been with your significant other for a while, chances are you know how they normally act — what type of foods they eat, how they react to challenges or surprises, how well they listen, and so on.

Sudden changes in body language, from facial expressions to patterns of speech, can be red flags for duplicitous behavior, according to research from Lillian Glass, a behavioral analyst who once worked with the Federal Bureau of Investigation to study how to spot signs of deceit.

“Your body experiences these types of changes when you’re nervous and feeling tense — when you lie,” she writes in her book, “The Body Language of Liars.”

Lookout for silence, personal attacks, or repeating the question.

One telltale sign of lying, says Glass, is a sudden inability to speak. This happens because our automatic nervous system often responds to stress by starving the mouth of saliva.

Another is veering into personal attacks rather than answering a question that’s been asked, write CIA veterans Philip Houston, Michael Floyd, and Susan Carnicero in their recent book, “Spy the Lie.”

And in a study published in 2011, UCLA professor of psychology R. Edward Geiselman found that people who are lying tend to repeat questions before answering them, “perhaps to give themselves time to concoct an answer,” he said in a press release.